U.S. patent application number 11/775286 was filed with the patent office on 2008-01-24 for mri-monitored equipment with built-in mr signal reception coil and signal emitter.
Invention is credited to Zeng He He, Jian Min Wang, Yang Wang.
Application Number | 20080021305 11/775286 |
Document ID | / |
Family ID | 38972329 |
Filed Date | 2008-01-24 |
United States Patent
Application |
20080021305 |
Kind Code |
A1 |
He; Zeng He ; et
al. |
January 24, 2008 |
MRI-MONITORED EQUIPMENT WITH BUILT-IN MR SIGNAL RECEPTION COIL AND
SIGNAL EMITTER
Abstract
In a system having a magnetic resonance imaging (MRI) apparatus
and MRI-monitored medical equipment, the MRI-monitored medical
equipment has an inductive coil built into the equipment that
receives magnetic resonance signals from a subject and generates
inductive electromagnetic signals according to the received
magnetic resonance signals. The magnetic resonance imaging system
has at least one reception coil that is positioned externally of
the MRI-monitored medical equipment and that is connected to the
magnetic resonance imaging system via a cable. The reception coil
receives the electromagnetic signals that are generated by the
inductive coil that is built into the medical equipment.
Inventors: |
He; Zeng He; (Shenzhen,
CN) ; Wang; Jian Min; (Shenzhen, CN) ; Wang;
Yang; (Shenzhen, CN) |
Correspondence
Address: |
SCHIFF HARDIN, LLP;PATENT DEPARTMENT
6600 SEARS TOWER
CHICAGO
IL
60606-6473
US
|
Family ID: |
38972329 |
Appl. No.: |
11/775286 |
Filed: |
July 10, 2007 |
Current U.S.
Class: |
600/411 |
Current CPC
Class: |
G01R 33/4814 20130101;
A61B 5/055 20130101; G01R 33/3642 20130101; A61B 6/462
20130101 |
Class at
Publication: |
600/411 |
International
Class: |
A61B 5/055 20060101
A61B005/055 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 19, 2006 |
CN |
200610088822.5 |
Claims
1. A magnetic resonance (MR) system comprising: a magnetic
resonance imaging (MRI) apparatus; MRI-monitored medical equipment;
said magnetic resonance imaging apparatus comprising a control unit
that monitors said MRI-monitored medical equipment; said
MRI-monitored medical equipment comprising an inductive coil fixed
in said MRI-monitored medical equipment that receives magnetic
resonance signals from a subject and generates electromagnetic
signals corresponding to the received magnetic resonance signals;
and said magnetic resonance imaging apparatus comprising at least
one receiving coil positioned externally of said MRI-monitored
medical equipment, said at least one receiving coil being connected
to said control unit via a cable, and said receiving coil receiving
said electromagnetic signals from said inductive coil of said
MRI-monitored medical equipment and supplying the received
electromagnetic signals to the control unit.
2. A system as claimed in claim 1 wherein said MRI-monitored
medical equipment comprises high intensity focused ultrasound knife
equipment, said high intensity focused ultrasound knife equipment
being disposed in a liquid in a container, and said inductive coil
being sealed and fixed in the liquid in said container.
3. A system as claimed in claim 2 wherein said inductive coil is a
planar coil disposed in a plane, and wherein said inductive coil is
disposed above said high intensity focused ultrasound knife
equipment and is oriented to cause ultrasonic waves emitted by said
high intensity focused ultrasound knife equipment to proceed
vertically through said plane.
4. A system as claimed in claim 3 wherein inductive coil is
positioned to avoid interaction by said inductive coil with said
ultrasonic waves by being oriented so that said ultrasonic waves
pass through a central region of said plane of said inductive
coil.
5. A system as claimed in claim 1 comprising a plug-in connection
connecting said cable to said receiving coil.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to the field of magnetic
resonance, particularly to the field of magnetic resonance imaging,
and specifically, to an apparatus for transmitting magnetic
resonance signals in MRI-monitored medical equipment.
[0003] 2. Description of the Prior Art
[0004] Various forms of therapeutic treatments can be applied to
the body of a human or other mammalian subject by applying energy
from outside the body. For example, when treatments are performed
by using hyperthermia techniques, ultrasonic or radio frequency
energy is applied externally to a subject's body to heat different
tissues. This is known as the high intensity focused ultrasonic
knife (HIFU) technique. The working principle of the technique is
that high-energy ultrasonic waves are emitted without contact and
enter a human body via a water medium coupling. The applied energy
can be focused to a very small spot within the human body so as to
heat the tissues at that spot to a temperature sufficient to create
a desired therapeutic effect, and to necrotize tissue at the focal
spot within a very short period of time. This technique can be
selectively used to destroy unwanted tissues within a body. For
example, tumors or other unwanted tissues can be destroyed by
applying heat, and the applied heat can heat the abnormal tissues
to a temperature sufficient to kill them without damaging normal
tissues nearby, with the temperature usually between 60.degree. C.
to 80.degree. C. Such a process is commonly referred to as "thermal
ablation". Other hyperthermia treatments include selectively
heating tissues so as to selectively activate a drug, or to promote
some other physiological changes in a selected part of the body of
a subject under the treatment. In other therapeutic methods, the
applied energy can be used to destroy abnormal objects or deposits
within a body such as, for example, in ultrasonic lithotripsy.
[0005] Magnetic resonance can be used in medical imaging for
diagnostic purposes. In magnetic resonance imaging (MRI)
procedures, a body region of the subject to be imaged is subjected
to a strong magnetic field. Radio frequency (RF) signals are
applied to the tissues of the subject within the imaging volume,
and under these conditions, atomic nuclei are excited by the
applied radio frequency signals and emit faint radio frequency
signals, which are referred to as magnetic resonance signals. By
superimposing appropriate gradients on the magnetic field during
the procedure, the magnetic resonance signals can be obtained
selectively from a limited region, such as a two-dimensional slice
of the subject's tissue. The frequency and phase of the signals
from different parts of the slice can be made to vary with their
positions in the slice. By using this known technique, it is
possible to demodulate the signals arising from different parts of
the slice, and to deduce from these signals the properties of the
tissues at each point of the slice.
[0006] Various proposals have been made to use magnetic resonance
to monitor and guide medical equipment, particularly during a
procedure of applying energy into a body. Certain magnetic
resonance procedures are temperature sensitive, so that magnetic
resonance data acquired by using these procedures will generate an
image in a MRI system, and indicate temperature changes in tissues,
so as to accomplish a therapeutic procedure. However, there are
always some problems when such medical equipment is used in
conjunction with an MRI system. Taking a HIFU treatment device as
an example, during the MRI imaging procedure, RF signals are
usually transmitted into a human body by a large body coil and this
large body coil receives magnetic resonance signals emitted from
the human body, and the MRI system makes use of these magnetic
resonance signals to generate an image. When using medical
equipment such as HIFU which requires very high precision imaging,
the signal-to-noise ratio during the imaging by such a large body
coil does not meet the requirements (the imaging quality of the
body coil is not very high due to the fact that the coil is too
large, and the bigger the coil is, the less ideal is the imaging
quality). Therefore the local imaging quality is not high. An
alternative is to acquire the magnetic resonance signals using a
fixed receiving coil (local coil), but there are many restrictions
in practical application. Since a fixed coil needs to be placed in
HIFU solution in order to receive the magnetic resonance signals
emitted from the body, and the fixed coil also needs to be
connected to a cable and to transmit the magnetic resonance signals
to the MRI processor for imaging, there is the problem of sealing
the coil and the cable. Moreover, the need to seal the cable and
the fixed coil in turn creates the problem of inconveniency in
moving the fixed coil, which further results in a restriction to
imaging range. All these problems are difficulties encountered when
using the fixed coil.
SUMMARY OF THE INVENTION
[0007] An object of the present invention is to provide an
apparatus for transmitting magnetic resonance signals in MRI-guided
medical equipment that avoids the aforementioned problems.
[0008] The above object is achieved in accordance with the present
invention in a magnetic resonance (MR) system having a magnetic
resonance imaging (MRI) apparatus and MRI-monitored medical
equipment, wherein the MRI-monitored medical equipment has an
inductive coil built into the equipment that receives magnetic
resonance signals from a subject and generates inductive
electromagnetic signals according to the received magnetic
resonance signals. The magnetic resonance imaging system has at
least one reception coil that is positioned externally of the
MRI-monitored medical equipment and that is connected to the
magnetic resonance imaging system via a cable. The reception coil
receives the electromagnetic signals that are generated by the
inductive coil that is built into the medical equipment.
[0009] The medical equipment can be high intensity focused
ultrasonic knife equipment. The high intensity focused ultrasonic
knife equipment is placed in liquid in a container, and the
inductive coil is sealed and fixed in the liquid in the
container.
[0010] The connection of the cable to the receiving coil is in a
plug-in manner.
[0011] The inductive coil can be positioned above the high
intensity focused ultrasonic knife equipment, so as to allow the
ultrasonic waves emitted by the high intensity focused ultrasonic
knife equipment to pass through the plane of the inductive coil
vertically.
[0012] The inductive coil is placed to avoid the ultrasonic waves
emitted by the high intensity focused ultrasonic knife equipment,
so as to allow the ultrasonic waves to pass through the central
plane of the inductive coil.
[0013] An advantage of the present invention is that the
compatibility between the MRI system and the medical equipment
guided is significantly improved, and the MRI real time detection
during a treatment becomes more convenient. The drawbacks in the
sealing and fixing of the previous coil and the cable are avoided,
and images of a better quality are provided during therapy.
Therefore, surgical operation effects of therapeutic equipment,
particularly the HIFU equipment, are improved. Furthermore, the
present invention is convenient to install, easy to maintain, and
the imaging quality and flexibility are improved by the coils of
various sizes for detecting corresponding positions, and the simple
mechanical devices also reduce malfunction rate.
DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a circuit diagram for an embodiment of the
inductive coil according to the present invention.
[0015] FIG. 2 is a circuit diagram for an embodiment of the
receiving coil according to the present invention.
[0016] FIG. 3 schematically illustrates an apparatus for
transmitting magnetic resonance signals to an MRI system in an
embodiment of the present invention with HIFU equipment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] The present invention is described in detail with reference
to the accompanying drawings.
[0018] When magnetic resonance signals are received by using a
fixed coil in the current MRI-monitored medical equipment, the coil
may need to be sealed or be moved flexibly, at such time an
inductive coupling coil can be used to achieve the functions of a
fixed coil, and hereinbelow, the detailed construction of the
present invention is described with an MRI system-guided HIFU
equipment as an example.
[0019] An inductive coupling coil is divided into two parts: an
inductive coil (shown in FIG. 1) is a standard LC resonance coil
for receiving magnetic resonance signals returning from a human
body and generating corresponding inductive electromagnetic waves.
The receiving coil is a common coil (shown in FIG. 2) for receiving
the electromagnetic wave signals from the inductive coil and
transmitting the same to the MRI system via a signal channel. The
inductive coil is relatively independent, and can be fixed at any
place in a water trough by one-step injection-molding. The best
place to position it is just above a HIFU transmitter where the
most magnetic resonance signals from a human body can be received.
There is no need for connecting to other equipment, and no
restriction by a cable, therefore there is no problem in connecting
a sealed cable. At the same time the sizes of inductive coils can
be tailored and replacement can be selected according to the size
of a therapeutic region. The receiving coil is connected by an
output cable for the connection to the control portion of the MRI
system. Due to the fact that it is far away from the human body
that emits the magnetic resonance signals, the reception of the
electromagnetic wave signals from the inductive coil will not be
disturbed. The position of the receiving coil is not restricted by
the HIFU equipment, so it is flexible to place and to move.
Therefore the shortcomings in the compatibility of the common RF
receiving coils in the HIFU, MRI are solved.
[0020] FIG. 3 shows an illustrative view of an apparatus for
transmitting magnetic resonance signals to an MRI system in the
application of an embodiment of the present invention in HIFU
equipment. A human body is positioned just underneath a liquid
container with the person's skin of an affected part contacting the
surface of the solution, which is preferably an aqueous solution.
The inductive coil needs to avoid the emitting pathway of the HIFU
equipment. Therefore, in the most preferred embodiment, the
ultrasonic waves emitted by the HIFU equipment pass through the
central plane of the inductive coil. The cable of the HIFU
equipment extends out of the solution to connect to the control
unit, which can be a control computer in the MRI system and which
controls the HIFU equipment and the inductive coil, as is
conventional. The MRI control unit controls the operation of the
HIFU device and the transmission of signals by the body coil. The
receiving coil is positioned outside the container for receiving
the electromagnetic wave signals transmitted by the inductive coil.
The receiving coil's cable is connected to the control unit of MRI
system, so that the receiving coil can be replaced according to the
imaging requirements, so as to improve the imaging quality and the
imaging range (allowing the distance for a human body to receive
the magnetic resonance signals to be increased). Thus the imaging
problem of the MRI system when used with the HIFU technique can be
solved. The imaging range may be changed as desired by replacing
different receiving coils, and as shown in FIG. 3, the position of
the receiving coil can be moved, so the position of the receiving
coil can be adjusted according to the needs for imaging, so as to
optimized it in order to obtain the maximum magnetic flux in the
inductive coil and to produce images of optimal angles and
effects.
[0021] An advantage of the present invention is that the
compatibility between the MRI system and the medical equipment
monitored thereby is significantly improved by the present
invention, and the MRI real time detection during a treatment
becomes more convenient. The drawbacks in the sealing and fixing of
the previous coil and the cable are avoided. Images of a better
quality are provided during therapy, therefore surgical operation
effects of therapeutic equipment, particularly the HIFU equipment,
are improved. Furthermore, the present invention is convenient to
install, easy to maintain, and the imaging quality and flexibility
are improved by the coils of various sizes for detecting
corresponding positions, and the simple mechanical devices also
reduce malfunction rate.
[0022] Although modifications and changes may be suggested by those
skilled in the art, it is the intention of the inventors to embody
within the patent warranted hereon all changes and modifications as
reasonably and properly come within the scope of their contribution
to the art.
* * * * *